The present invention relates to an information playback apparatus for providing playback of audio information such as music or sound in conjunction with editing effects.
The present application claims priority from Japanese Application No. 2001-150928, the disclosure of which is incorporated herein by reference for all purposes.
For playback of analog record discs such as LPs with analog record players, conventional performance techniques are known which provide various editing effects for playback of sounds by forcefully changing the rotational direction and speed of the analog record disc through hand operations.
For example, a producer called a disc jockey may be seen such as in discotheques who touches an analog record disc during playback with an analog record player in order to forcefully rotate the disc at an rpm different from the one originally intended for the disc in the forward or reverse rotational direction. The producer thereby produces an imitation sound called a scratching sound (an imitation sound, such as “squeaking” and “rattling”).
On the other hand, storage media such as CDs (Compact Disc) or DVDs (Digital Versatile Disc), on which information is stored in digital form, have come into actual use as the digital technology moves forward. It is now therefore difficult to provide such editing effects for those storage media through the same hand operations as for the conventional analog record disc.
That is, in the case of the analog record disc, audio signals such as music are allowed to remain unchanged to be continuously stored along the record track, thus making it possible to establish one to one correspondences between the position of the analog record disc to be read (or scanned) with a record stylus and the sound to be read. It is therefore possible to provide editing effects through hand operations as desired.
However, in the case of storage media such as CDs or DVDs on which information is stored in digital form, a special digital technology is employed to record or read the information which cannot be made known to human sense by intuition. For example, it is not possible to provide editing effects as desired for a CD during playback with a CD player even through the hand operations as for the analog record disc.
In particular, it is stipulated in the standards for CD or DVD players that their optical read device or pickup is to read information and play back the sound while the CD or DVD is being rotated in the predetermined rotational direction with respect to the pickup. Thus, it is not standardized that information is to be read in the reverse order to play back the sound while the CD or DVD is being rotated in the reverse rotational direction with respect to the pickup. Accordingly, turning the CD or DVD merely in the direction opposite to the predetermined direction through hand operations would cause information to be improperly read and played back, thereby making it impossible to produce an imitation sound called a scratching sound.